Method for Topically Treating Actinic Keratosis with ingenol 3-(3,5-diethylisoxazole-4-carboxylate)

ABSTRACT

The invention relates to the topical treatment of actinic keratosis with ingenol 3-(3,5-diethylisoxazole-4-carboxylate).

FIELD OF THE INVENTION

The invention relates to the topical treatment of actinic keratosis with ingenol 3-(3,5-diethylisoxazole-4-carboxylate).

CROSS-REFERENCE RELATED APPLICATIONS

This application for U.S. patent claims priority to EP patent application No. 13190223.1, filed 25 Oct. 2013, the contents of which is incorporated herein by reference in its entirety, EP patent application No. 14161730.8, filed 26 Mar. 2014, the contents of which is incorporated herein by reference in its entirety, and EP patent application No. 14165659.5, filed 23 Apr. 2014, the contents of which is incorporated herein by reference in its entirety.

BACKGROUND OF THE INVENTION

The active compound, ingenol 3-(3,5-diethylisoxazole-4-carboxylate), of the present invention has previously been described in PCT/DK2011/000154. Ingenol 3-(3,5-diethylisoxazole-4-carboxylate) has previously been studied with respect to safety and tolerability for field therapy in 25 cm² on 4 separate areas on the forearm in concentrations of 0.025%, 0.05% and 0.075% in a gel formulation. Picato® which is launched in many countries around the world for treatment of actinic keratosis on the face or balding scalp has a dosage regimen of two or three days depending on the location of the actinic keratosis. According to the FDA label for Picato®, the size of the treatment area is limited to about 25 cm2 (2 inches×2 inches).

SUMMARY OF THE INVENTION

The present invention provides a topical treatment regimen for actinic keratosis (AK) which is of short duration and applicable to a large skin area, i.e. full face or up to 250 cm² on the body or balding scalp. The treatment is simple by the two day regimen on all body parts, whereas the applied dosage may vary, such that body locations which are considered difficult to treat may be treated with a higher dosage strength in accordance with the present invention. The topical treatment methods of the present invention are effective in treating nonhyperkeratotic actinic keratosis. The novel topical treatments provide for acceptable side-effects in terms of measured local skin reactions (LSR). The present invention also presents a preferred topical formulation for the ingenol 3-(3,5-diethylisoxazole-4-carboxylate).

The present invention provides a method of treating a subject diagnosed with actinic keratosis, said method comprising applying an effective amount of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) to a treatment area on the body, scalp or face for two days to achieve at least partial clearance of the actinic keratosis, wherein the two day treatment is preferably two consecutive days.

DETAILED DESCRIPTION OF THE INVENTION

From Picato® and other topical agents used in the treatment of actinic keratosis, it is well known that differences in treatment efficacy exists between different anatomical regions. Regions like scalp, trunk (except chest) and extremities are more difficult to treat than the face. From the Picato® studies, it has been shown that local skin reactions after a given dose are milder on difficult to treat anatomical regions than on anatomical regions more easily treated with the compound.

The present invention simplifies prior and existing treatments by a simple two day regimen independent of the location of the actinic keratosis. Potentially, the concentration of the topically applied formulation will vary depending on the location of the actinic keratosis.

The present invention describes treatment of actinic keratosis on an area of up to 250 cm² on the face or a contiguous area on the scalp, chest, trunk or body. The lesions are not of atypical clinical appearance such as for example hypertrophic, hyperkeratotic or cutaneous horns and/or recalcitrant diseases, such as non-responding to cryotherapy on two previous occasions.

Local skin reactions (LSRs) occurs sometimes in the treated area. Often LSRs are quantified by a scale evaluating the following types of skin reactions: erythema, flaking/scaling, crusting, swelling, vasiculation/postulation, and erosion/ulceration which are categorized into categories 0-4 depending on the severity of the reactions.

The topical medication applied is either a gel or a cream. The cream formulation comprises:

Benzyl alcohol, macrogol 30 dipolyhydroxystearate, isohexadecane, isopropyl myristate, PPG-11 stearyl ether, glycerol, magnesium sulphate heptahydrate, citric acid, sodium citrate and water.

The gel formulation comprises:

isopropyl alcohol, hydroxyethyl cellulose, benzyl alcohol, citric acid monohydrate, sodium citrate dihydrate and water.

The active compound is ingenol 3-(3,5-diethylisoxazole-4-carboxylate).

The present invention relates to the treatment of actinic keratosis lesions on face, chest, trunk or body by a once daily, two day treatment in a treatment area of a size up to 250 c^(m2).

The present invention relates to the topical treatment of actinic keratosis lesions on the full face or in an area of approximately 250 cm² on the chest, trunk or body by a once daily, two day treatment.

In one embodiment according to the present invention, the two day treatment is two consecutive days.

In another embodiment according to the present invention, the present invention provides application of ingenol 3-(3,5-diethylisoxazole-4-carboxylate) in a concentration of about 0.0015%, about 0.003%, about 0.006%, about 0.012%, about 0.018%, about 0.025%, about 0.037%, about 0.050%, about 0.075% or about 0.1% In another embodiment according to the present invention, the topical application of ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is in a concentration of 0.006%, 0.012% or 0.018%. In an embodiment of the concentration is 0.018%.

In yet another embodiment according to the present invention, the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is formulated into a gel or a cream. In still another embodiment according to the present invention, the present invention provides a method of topically treating a subject diagnosed with actinic keratosis, said method comprising topically applying an effective amount of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) to a treatment area for two days to achieve reduction in the number of actinic keratosis lesions in the treated area, wherein the treatment area is of a size of up to about 250 cm².

In yet another embodiment, the present invention provides the topical method as above wherein the two days treatment is two consecutive days.

In a further embodiment, the present invention provides the topical method according to the above, wherein the area treated is full face. In another embodiment, the present invention provides the topical method according to the above, wherein the treated area is up to approximately 250 cm².

In still another embodiment, the present invention provides the topical method according to the above, wherein the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is formulated in a gel.

In yet another embodiment, the present invention provides the topical method according to the above, wherein the gel is formulated with the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) in concentrations of about 0.0015%, about 0.003%, about 0.006%, about 0.012%, about 0.018%, about 0.025%, about 0.037%, about 0.05%, about 0.075% or about 0.1%.

In a further embodiment, the present invention provides the method according to the above, wherein the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is formulated in a cream.

In yet another embodiment, the present invention provides the topical method according to the above, wherein the cream is formulated with the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) in concentrations of about 0.0015%, about 0.003%, about 0.006%, about 0.012%, about 0.018%, about 0.025%, about 0.037%, about 0.05%, about 0.075% or about 0.1%.

In an embodiment of the present invention, the amount of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) topically applied is about 4.5 μL medication at a concentration of about 0.0015%/per day/250 cm² treated area.

In an embodiment of the present invention, the amount of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) topically applied is 4.5 μL medication at a concentration of 0.003%/per day/250 cm² treated area.

In an embodiment of the present invention, the amount of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) topically applied is 4.5 μL medication at a concentration of 0.006%/per day/250 cm² treated area. In an embodiment of the present invention, the amount of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) topically applied is 4.5 μL medication at a concentration of 0.012%/per day/250 cm² treated area.

In an embodiment of the present invention, the amount of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) topically applied is 4.5 μL medication at a concentration of 0.018%/per day/250 cm² treated area.

In an embodiment of the present invention, the amount of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) topically applied is 4.5 μL medication at a concentration of 0.025%/per day/250 cm² treated area.

In an embodiment of the present invention, the amount of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) topically applied is 4.5 μL medication at a concentration of 0.037%/per day/250 cm² treated area.

In an embodiment of the present invention, the amount of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) topically applied is 4.5 μL medication at a concentration of 0.05%/per day/250 cm² treated area.

In an embodiment of the present invention, the amount of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) topically applied is 4.5 μL medication at a concentration of 0.075% active compound/per day/250 cm² treated area.

In an embodiment of the present invention, the amount of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) topically applied is 4.5 μL medication at a concentration of 0.1% active compound/per day/250 cm² treated area.

EXAMPLE

Subjects who qualify for the trial must have 5 to 20 clinically typical, visible and discrete actinic keratosis on the face or on either the face or within a contiguous area of approximately 250 cm² on the chest. Subjects will be randomized to active compound, gel or cream in a 1:1 ratio, when applicable. Randomization will be stratified by dose level.

Part 1: Trial medication will be applied to full face once daily for two consecutive days until the maximum tolerated dose has been reached for each formulation. Up to nine different doses of active compound in gel and cream may be investigated in cohorts of 3 to 12 subjects. Pre-defined grades of Local Skin Responses (LSRs) will constitute dose limiting toxicity (DLT). The maximum tolerated dose is defined as the highest dose level at which less than 4 out of 12 subjects experience a Dose limiting toxicity. The doses will be administered in an escalating manner following review of safety and tolerability data performed by the dose escalation committee. Evaluation of the safety and tolerability data will be performed after Visit 5/day 8. Then subjects will be followed for 8 weeks after first application of investigational product. Part 1 of the trial will include cohorts of 3-12 subjects. There will be up to 9 cohorts for each of the two formulations. The number of subjects in each cohort will depend on the number of DLTs. The maximum tolerated dosages will be confirmed in cohorts of 12 subjects. Part 2 of the trial includes a total of 372 subjects: 62 subjects in each of the 4 active treatment arms and 62 subjects in each of the two vehicle arms. To be included in the trial part 1 the subjects must be at least 18 years of age with about 5-20 clinically typical, visible and discrete actinic keratosis on the face. To be included in the trial part 2 the subjects have 5-20 clinically typical, visible and discrete actinic keratosis either on the face or within a contiguous area of approximately 250 c^(m2) on the chest. Exclusion criteria is incompletely healed wound, basal cell carcinoma or squamous cell carcinoma within 5 cm of treatment area, or prior treatment with ingenol mebutate gel on the treatment area, or atypical clinical appearance on the lesions such as hypertrophic, hyperkeratotic or cutaneous hors, and/or recalcitrant disease such as non-responding to cryotherapy on two previous occasions. Also other skin conditions, cosmetic procedures or other disease or medication which could interfere with the evaluation of the trial medication or the assessments of the treated area are exclusion criteria, as is other disease or medical conditions which make the subject unsuitable to participate in the trial. The patients are scheduled for 7 visits: Visit 1: within 35 days prior to day 1 Visit 2: day 1 (application of trial medication)

Visit 3: day 2 (application of trial medication)

Visit 4: days 3 Visit 5: day 8(±1 day) Visit 6: week 2 Visit 7: week 8. LSRs are evaluated at all visits following visit 1. Efficacy analyses will be based on the full analysis set, which will be defined as all randomized subjects. Per protocol analysis set will be used as an efficacy subset and will be defined as subjects in the full analysis set who complete the study without major protocol deviations. Safety analyses will be based on the safety analysis set, which is defined as all subjects who receive at least one application of trial medication and have safety information available post treatment.

At visit 7 in week 8 the ratio of number of lesions at week 8 relative to baseline will be tabulated by treatment group and analyzed using a negative binomial regression on actinic keratosis count at week 8 with the log baseline value as an offset variable and treatment group and analysis site as factor. The rate ratios and the corresponding 95% confident intervals will be estimated from this model comparing the active groups pairwise.

The incidence and grade of LSRs will be summarized by treatment arm overall at each visit and by anatomical location. Local skin response grades will be summarized by frequency counts and descriptive statistics by treatment arm for each of the six individual LSRs: erythema, flaking/scaling, crusting, swelling, vesiculation/postulation, and erosion/ulceration.

A composite score will be obtained by summing the six individual LSR scores at each visit. The composite score and change from baseline will be summarized by treatment arm at each visit using descriptive statistics.

INCORPORATION BY REFERENCE

The entire contents of all patents, published patent applications and other references cited herein are hereby expressly incorporated herein in their entireties by reference.

Equivalents

Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, numerous equivalents to the specific procedures described herein. Such equivalents are considered to be within the scope of this invention and are covered by the following claims. 

What is claimed is:
 1. A method of treating a subject diagnosed with actinic keratosis, said method comprising topically applying an effective amount of ingenol 3-(3,5-diethylisoxazole-4-carboxylate) to a treatment area for two days.
 2. The method of claim 1, wherein the method provides a reduction in the number of actinic keratosis in the treated area.
 3. The method of claim 1, wherein the two day treatment is two consecutive days.
 4. The method of claims 1-3, wherein the treated area is located on the face, chest, trunk or body.
 5. The method of claim 1-4, wherein the treated area is up to about 250 cm2
 6. The method of any of the claim 1, wherein the effective amount of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is applied from a dosage strength formulation of between about 0.01% and about 0.1%.
 7. The method of any of the claim 2, wherein the effective amount of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is applied from a dosage strength formulation of between about 0.01% and about 0.1%
 8. The method of any of the claim 3, wherein the effective amount of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is applied from a dosage strength formulation of between about 0.01% and about 0.1%.
 9. The method of any of the claim 4, wherein the effective amount of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is applied from a dosage strength formulation of ingenol 3-(3,5-diethylisoxazole-4-carboxylate) of between about 0.01% and about 0.1%.
 10. The method of any of the claim 5, wherein the effective amount of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is applied from a dosage strength formulation of ingenol 3-(3,5-diethylisoxazole-4-carboxylate) of between about 0.01% and about 0.1%.
 11. The method of claim 1, wherein the dosage strength formulation of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is about 0.018%, about 0.025%, about 0.037%, about 0.05%, about 0.075% or about 0.1%.
 12. The method of claim 2, wherein the dosage strength formulation of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is about 0.018%, about 0.025%, about 0.037%, about 0.05%, about 0.075% or about 0.1%.
 13. The method of claim 3, wherein the dosage strength formulation of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is about 0.018%, about 0.025%, about 0.037%, about 0.05%, about 0.075% or about 0.1%.
 14. The method of claim 4, wherein the dosage strength formulation of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is 0.018%, 0.025%, 0.037%, 0.05%, 0.075% or 0.1%.
 15. The method of claim 5, wherein the dosage strength formulation of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is about 0.018%, 0.025%, 0.037%, 0.05%, 0.075% or 0.1%.
 16. The method of claim 1, wherein the dosage strength formulation of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is about 0.006%, about 0.012% or about 0.018%.
 17. The method of claim 2, wherein the dosage strength formulation of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is about 0.006%, about 0.012% or about 0.018%.
 18. The method of claim 3, wherein the dosage strength formulation of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is about 0.006%, about 0.012% or about 0.018%.
 19. The method of claim 4, wherein the dosage strength formulation of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is about 0.006%, about 0.012% or about 0.018%.
 20. The method of claim 5, wherein the dosage strength formulation of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is about 0.006%, about 0.012% or about 0.018%.
 21. The method of a claim 1, wherein the dosage strength formulation of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is about 0.018%.
 22. The method of a claim 2, wherein the dosage strength formulation of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is about 0.018%.
 23. The method of a claim 3, wherein the dosage strength formulation of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is about 0.018%.
 24. The method of a claim 4, wherein the dosage strength formulation of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is about 0.018%.
 25. The method of a claim 5, wherein the dosage strength formulation of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is about 0.018%.
 26. The method of any of the claims 1-3, wherein the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is formulated in a gel.
 27. The method of claim 4, wherein the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is formulated in a gel.
 28. The method of any of the claims 5-25, wherein the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is formulated in a gel.
 29. A method of treating a subject diagnosed with actinic keratosis, said method comprising topically applying an effective amount of ingenol 3-(3,5-diethylisoxazole-4-carboxylate) to a treatment area for two consecutive days, wherein, said method provides a reduction in the number of actinic keratosis lesions in the treatment area, wherein, the treatment area is of a size up to about 250 cm², and wherein, the dosage strength of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is between about 0.006% and about 0.018%.
 30. The method of claim 29, wherein the dosage strength of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is about 0.006%.
 31. The method of claim 29, wherein the dosage strength of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is about 0.012%.
 32. The method of claim 29, wherein the dosage strength of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is about 0.018%.
 33. The method of claim 1-3 or 29, wherein the amount of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) topically applied is about 4.5 μL medication at a concentration of about 0.0015%/per day/250 cm² treated area.
 34. The method of claim 1-3 or 29, wherein the amount of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) topically applied is 4.5 μL medication at a concentration of 0.003%/per day/250 cm² treated area.
 35. The method of claim 1-3 or 29, wherein the amount of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) topically applied is 4.5 μL medication at a concentration of 0.006%/per day/250 cm² treated area.
 36. The method of claim 1-3 or 29, wherein the amount of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) topically applied is 4.5 μL medication at a concentration of 0.012%/per day/250 cm² treated area.
 37. The method of claim 1-3 or 29, wherein the amount of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) topically applied is 4.5 μL medication at a concentration of 0.018%/per day/250 cm² treated area.
 38. The method of claim 1-3 or 29, wherein the amount of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) topically applied is 4.5 μL medication at a concentration of 0.025%/per day/250 cm² treated area.
 39. The method of claim 1-3 or 29, wherein the amount of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) topically applied is 4.5 μL medication at a concentration of 0.037%/per day/250 cm² treated area.
 40. The method of claim 1-3 or 29, wherein the amount of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) topically applied is 4.5 μL medication at a concentration of 0.05%/per day/250 cm² treated area.
 41. The method of claim 1-3 or 29, wherein the amount of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) topically applied is 4.5 μL medication at a concentration of 0.075% active compound/per day/250 cm² treated area.
 42. The method of claim 1-3 or 29, wherein the amount of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) topically applied is 4.5 μL medication at a concentration of 0.1% active compound/per day/250 cm² treated area.
 43. The method of claim 1-3 or 29, wherein the amount of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) topically applied is in concentrations of between about 0.0015% about 0.1%.
 44. The method of claim 1-3 or 29, wherein the amount of the ingenol 3-(3,5-diethylisoxazole-4-carboxylate) topically applied is in concentrations of about 0.0015%, about 0.003%, about 0.006%, about 0.012%, about 0.018%, about 0.025%, about 0.037%, about 0.05%, about 0.075% or about 0.1%. 